A new start for my main tank?

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Viktor, thanks for that ^ post. I am embarrassed to admit that I have done so little research on goldfish and their kin that I didn't even know that Crucians (and Prussians) were actual species of carp! I don't know where I got the idea that they were just line-bred varieties of Common Carp, much like Mirror Carp, but that's what I have "known" :) for ages.

I also thought...without really thinking about it :)...that Carassius auratus was a natural species and all of the varieties of it merely line-bred man-made creations.

I also didn't do some more thinking/reading and assumed that koi were just line-bred Cyprinus carpio, rather than yet another species.

So that one post delivered a right cross, a left cross and then an uppercut to the fragile jaw of my wisdom regarding goldfish and their relatives. Phew! I'll bet that I "learned" all that other stuff from the pages of one of the 500,000 little pamphlet-style books put out back in the day by TFH. Between Herbert R. Axelrod and his minion Mervin Roberts, I learned a lot of info back then that just wasn't so. :)
 
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:) I am not professing from a cathedra. I need to be corrected or affirmed too in what I said.

As we saw, Crucian sounds related to Latin Carassius, and to Russian/Slavic Karass, and to German (Prussian) Karausche... Neither Cyprinus nor Carpio are phonetically related to Crucian / Carassius. FWIW.

JJ: " I also thought...without really thinking about it :)...that Carassius auratus was a natural species and all of the varieties of it merely line-bred man-made creations."
V: That still may be in my naive head. I am fuzzy on that aspect, that is whether auratus is/was real and is/was really GOLD verbatim, and all the red and orange white and blotchy fish are the manmade diversions.

Taxonomy and ichthyology did make a lot of progress in the past 25-50 years :)
 
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There are two common species of Carassius in Europe:

[1] Crucian Carp / Gold carassius / Round carassius / Common carassius = Carassius carassius

Carassius: Latinization of karass, karausche, European crucian carp Actinopterygii (ray-finned fishes) > Cypriniformes (Carps) > Cyprinidae (Minnows or carps) > Cyprininae Max length 64 cm TL male/unsexed; common length : 15 cm TL male/unsexed; max. published weight: 3 kg; max. reported age: 10 years.

FWR 55-64 (80?) cm; 4-5 (6?) kg; 30 years. Freshwat.; brackish; demersal; potamodromous; depth 5 - ? m Temperate 2 - 22°C

69°N-35°N

10°W - 169°E Eurasia: North, Baltic, White, Barents, Black & Caspian Sea basins; Aegean Sea basin only in Maritza drainage; eastward to Kolyma drainage (Siberia); westward to Rhine & eastern drainages of England. Absent from North Sea basin in Sweden & Norway. In Baltic basin north to about 66°N. Widely introduced to Italy, England & France but possibly often confused with Carassius gibelio. At least one country reports adverse ecological impact after introduction. Adults occur in shallow ponds, lakes rich in vegetation & slow moving rivers. They burrow in mud in the drought or during winter. Usually restricted to densely vegetated backwaters & oxbows of lowland rivers. Can survive organic pollutants, cold, high temps & very low O2 conc. during summer & under ice cover. Feeds all day but mainly at night on plankton, benthic invertebrates, plant materials & detritus. Usually does not occur in waters with rich ichthyofauna & abundant predatory species, but very abundant in the absence of other fish species. Spawns in dense submerged vegetation. There is a gradual but continuing extirpation in many water bodies, esp. in Danube drainage & central Europe, possibly to due competition with introduced Carassius gibelio. Fisheries: highly com; a/c: com; game; aquar.: com. Least Concern


[2] Silver Crucian Carp / Giebel / Prussian Carp / Silver carassius = Carassius gibelio

Carassius: Latinization of karass, karausche, European crucian carp Actinopterygii (ray-finned fishes) > Cypriniformes (Carps) > Cyprinidae (Minnows or carps) > Cyprininae Max 35 cm SL male/unsexed; com. 20 cm TL; max. publ. w. 3 kg; max. rep. age: 10 years.

FWR 58 cm; 5 kg; 30 years. Freshwat.; brackish; benthopelagic; pH 7.1 - 7.5; dH 12 - ?; potamodromous Temperate 10 - 20°C;

62°N - 35°N,

10°W - 155°E Eurasia: usually considered native from central Europe to Siberia or introduced to Europe from eastern Asia. Clear & definite data on original distribution in Europe are not available due to introduction, confusion with Carassius auratus & complex reproduction. At present, widely distributed & commonly stocked together with Cyprinus carpio which is transported t/o Europe. Inhabits a wide variety of still water bodies & lowland rivers, usually associated with submerged vegetation or regular flooding. Can strongly tolerate low O2 concentrations & pollution. Lake dwelling individuals move into river mouths to avoid low O2 water in winter. Feeding larvae & juv. occur in high-complexity habitats as reed belts. Feeds on plankton, benthic invertebrates, plant material & detritus. Spawns in shallow, warm shores on submerged vegetation. Able to reproduce from unfertilized eggs (gynogenesis). Eastern European or wild form of the goldfish. Fisheries: minor com. Not Eval.


[3] Goldfish = Carassius auratus auratus / Carassius auratus

Carassius: Latinization of , karass, karausche, European crucian carp Actinopterygii (ray-finned fishes) > Cypriniformes (Carps) > Cyprinidae (Minnows or carps) > Cyprininae Max 32 cm SL m./u.; com. 10 cm TL; 41 years. 40 cm, 2.3 kg (Pract. Fishkeep. 2010).

FWR 50-62 cm; 3-4 (5?) kg; 50+ years. Freshwater benthopelagic; pH 6.0 - 8.0; dH 5 - 19; potamodromous; depth ? - 20 m Subtropical ? - 41°C

53°N-22°N Asia: central Asia & China, & Japan. Introduced t/o the world. Asian form of the goldfish. Several countries report adverse ecological impact after introduction. Inhabit rivers, lakes, ponds & ditches with stagnant or slow-flowing water. Occur in eutrophic waters, well vegetated ponds & canals. Live better in cold water. Feed mainly on plankton, benthic invertebrates, plant material & detritus. Goldfish lay eggs on submerged vegetation. Females spawn multiple times during the spawning period. Oviparous, with pelagic larvae. Max. recorded salinity is 17 ppt, but unable to withstand prolonged exposure >15 ppt. Used as an experimental species. Edible but rarely eaten. Aquar. keeping: in groups of 5 or more; min. tank size 1 m. Not Eval.



Perhaps Japan has their own species of common Carassius. Crucian carp are Carasius carassius from northern Europe, also a favorite and most spread and fished for fish in my home country. I fished all my younger years for them and carp too.

Perhaps I am wrong but i think goldfish is just a selectively bred for 5000 years Carassius carassius that became C. auratus, or maybe some very closely species out of Eastern Asia, likely the gibelio?

Koi BTW are a selectively bred far-eastern carp species Cyprinus rubrofuscus or Amur river carp, not the common carp Cyprinus carpio.
Huh... you learn something new every day, lol. Had no idea there were two sorts of crucians, or even two "common" carps. I was told that the crucians in Korea were all a Japanese species, but in hindsight I never looked into the matter much; based on what you provided I assume they were really C. gibelio. They really were fun to catch; I always collected them in plastic traps and small seines as a kid- never had much luck fishing for them; think I have some of those ridiculously tall, spindly bobbers used when fishing for them still.
The existence of C. rubrofuscus as a separate species really shocked me; had no idea the East Asian sort were a completely different species- always had a hunch, but saying that now seems redundant in hindsight.
I do recall reading some studies years ago out of boredom that claimed C. auratus were the result of line-bred Carassius of some sort. Thought it was rather odd how humans can create taxonomically-valid species simply via selective breeding, but maybe I'm misunderstanding something.
 
Yeah, I get that, Viktor, but what you stated seems very believable and more trustworthy than what I saw in a 50-year-old wrinkled-up copy of "Goldfish as Pets" back before we landed on the moon. :)

Crucian Carp in particular seems obviously distinguishable from Goldfish and Common Carp simply by tail and dorsal fin shape. I just literally never thought about it.

Taxonomy is weird. Certainly, it's a necessary part of the study of zoology, but many specialists are IMHO more concerned with renaming and reorganizing genera and species largely because they will then be immortalized as the latest and greatest in a line of thinkers, all of whom got it "wrong" before that new guy came along.

I was looking over the stock list of a large local importer/distributor/retailer of aquarium fish, and I was struck by how few of the old "classic" fish still have the same scientific designations as they did back when I first learned them. Species whose names remain the same as they were a few decades back are in the minority, compared to those whose names and even genera have changed one or multiple times.

Cichlids are among the worst sufferers in this regard. Back when I started in the hobby, just about everything was Cichlasoma, with a few exceptions. One of the exceptions was Aequidens. Today, most of those long-ago Cichlasomas have been split off into a large number of "new" genera...and many of those old Aequidens are now...wait for it...Cichlasoma!

Yes, yes, I know...DNA analysis has now nailed down what is related to what and how closely, so there will need to be changes in taxonomy meant to reflect this. But DNA doesn't draw hard lines here and there on the cichlid family tree that categorically state "This is where this genus ends, and where that one begins!" DNA shows the relative relationships of the various fish, how far back one splits off from another, etc. It illustates the spectrum and shows where on it each species sits.

The actual game of names is entirely artificial. :)
 
I'd personally not throw away a baby with the water, so to speak, by speaking too generally about taxonomy. I think what they do is valuable but like all science, it evolves all the time. It's a living thing.

Sure there are egos and sometimes even lies involved but I prefer to think that in a peer-reviewed science it is kept in check and rooted out sooner or later.

Plus there is as always a spectrum of opinions: splitters vs lumpers and all those in between :)

zsd0010505780005.jpglumpers_and_splitters.png
 
I would "prefer to think" that as well...but my generally dismal view of most of my fellow Homo sapiens makes that difficult or even impossible.

We are still Homo sapiens, aren't we? :)
 
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I would "prefer to think" that as well...but my generally dismal view of most of my fellow Homo sapiens makes that difficult or even impossible.

We are still Homo sapiens, aren't we? :)
I think we are just Homo now. We've divorced from Sapience, so this last name is in the past. Maybe we should go back to Homo Erectus.
 
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Another winter has come and (mostly) gone, and the basement goldies are looking good. The biggest are about 7 inches or so, and the small number of last year's fry that were lucky enough to make it into the big tank are all in the 1.5 to 2 inch range. This tank has been at 50f to 55f for most of the winter, has now begun to rise and is about 60f currently. It gets at least one water change of at least 90% or more each week. It's filtered with a large sump and wet-dry filter, and has the initial pre-filter stage of the mechanical filtration replaced several times weekly, or even daily if I am feeling industrious. The fish are fed lightly every day, an assorted diet of various flakes, pellets, frozen food, etc. and their appetite and activity level has remained good all winter. They spend their free time (which is, of course, all of their time...) picking up mouthfuls of the pool filter sand substrate, chewing it thoughtfully and then spitting it out. It builds up in drifts in the preferred spitting-out locations, and I periodically push it back more or less where I want it. For entertainment, they often try to steal a big algae wafer out of the mouth of the big Uruguayan pleco that lives with them; they never succeed, and he never acknowledges them.

In other words...these fish are maintained the way I feel that all fish should be kept: fed a good diet and kept in clean conditions with always-fresh water. Simple, really, and inevitably effective.

But...there are other goldfish down in the basement who don't have it quite so good. I overwinter a bunch of potted emergent plants, mostly papyrus, some wild garlic, and a few others, in a half-filled round stock tank. The tank is brightly illuminated and the plants seem to overwinter quite nicely in the cool basement air. Living in the water surrounding the pots is a handful of goldfish fry, siblings of the ones in the main tank. They have had no water changes all winter, just top-ups to replace evaporation. They get a tiny sprinkle of food a couple times per week; I doubt that any of it makes its way to the bottom during the ensuing feeding frenzy. The bottom is devoid of substrate, but is covered with a thick layer of detritus and mulm; aquarium keepers like to refer to this stuff in these terms because it sounds as though it's some valuable commodity that we nurture...but my granddaughters, with the honesty of youth, know what it is and call it by its correct name: fish poop.

This group of outlaws was introduced to the stock tank by the simple expedient of grabbing a big handful of guppy grass from the pond last fall and throwing it into the stock tank. It grows like wildfire, must be thinned on a regular basis, and the goldfish fry that came with it are now, surprisingly, just as big (all around 1.5 to 2 inches) as their lovingly nurtured siblings in the main tank, and look just as fat and healthy and happy. They're tough.

Pretty bad, huh? But wait...there's more...

In my den is a 30-ish gallon tank housing my Stinkpot turtle. He grew up with fish, and doesn't bother them, but the past few years he has been alone. He's pretty close to adult sized now, carapace length about 4 inches. He is fed a couple times weekly, in a separate bucket in which he stays until after his post-meal poop. His tank water is drained down to about 1/4-inch deep at least weekly, during feeding times, and replaced with clean fresh water. Bare ceramic tile bottom...almost no decor...and no plants, despite my efforts, because he eats 'em all. But last fall, I tossed in a handful of Guppy Grass harvested from my outdoor pond during its winterization cleanup. I assumed he'd mow it down immediately, but for some reason he doesn't like it and it is growing like crazy. It appears to have had a couple of goldfish fry in it when I threw it in; I noticed them a few days later, when they were very tiny, and didn't think much about them.

They're still in there; their diet consists of algae, turtle poop and (maybe) Guppy Grass. I've never actually seen them eat the GG, but can't discount the idea. I do know for a fact that I have never introduced any food of any kind into this tank since well before they ever appeared.

And... they are indistinguishable in size, activity and general health from the other ones in the other tanks. They are never fed, they flop around on their sides in a fraction of an inch of water during water changes, and in general have never had their asses kissed in any way, shape or form...and they look great!

Honestly...how can anybody not love goldfish? And now they are on the verge of ushering in a new paradigm in fish-nutrition thought and wisdom! :)
 
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When will you move them back outside?
 
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